Intel Core i3-9320 vs Intel Core i5-6600K Comparison

The Intel Core i3-9320 is the outright winner in every direct benchmark comparison against the Intel Core i5-6600K, making the older Skylake part the clear underdog in this matchup. The data from the head-to-head suite shows a consistent performance gap of roughly 14% across all six Cinebench tests, favoring the newer Coffee Lake chip. While the i5-6600K holds its own in overall average benchmark scores, the i3-9320’s superior clock speeds and newer architecture deliver a decisive and uniform victory in every measured workload.

Head-to-Head Benchmarks

The benchmark results are unambiguous: the Intel Core i3-9320 wins all six head-to-head comparisons, with the Intel Core i5-6600K failing to claim a single victory. The most significant margin appears in Cinebench R15 multicore, where the i3-9320 scores 630 against the i5-6600K’s 540, a 14.3% difference. This pattern of dominance repeats across every iteration of Cinebench, indicating that the i3-9320’s advantage is not workload-specific but a general performance lead.

In single-core tests, the i3-9320 continues its winning streak. Cinebench R15 single-core shows the i3-9320 at 88 points versus the i5-6600K’s 76, a 13.6% gap. The newer Cinebench R20 single-core test tells a similar story, with the i3-9320 scoring 370 compared to the i5-6600K’s 317, a 14.3% difference. These single-threaded results are particularly telling, as they highlight the i3-9320’s higher base and boost clocks of 3.70 GHz and 4.40 GHz, respectively, against the i5-6600K’s 3.50 GHz and 3.90 GHz.

The multi-core tests follow the same trajectory. Cinebench R20 multicore sees the i3-9320 at 2626 points, while the i5-6600K manages 2252, a 14.2% lead. In Cinebench R23 multicore, the i3-9320 posts 6254 versus the i5-6600K’s 5363, again a 14.2% margin. The single-core version of Cinebench R23 shows the i3-9320 at 882 and the i5-6600K at 757, a 14.2% difference. The consistency of these deltas — all hovering between 13.6% and 14.3% — suggests a fundamental architectural and clock-speed advantage rather than a test-specific anomaly.

Looking at the broader average benchmark scores, the two CPUs are nearly identical. The i5-6600K has an average benchmark score of 1816, while the i3-9320 sits at 1808. This places them as direct rivals, with the i5-6600K holding a mere 0.4% edge in this aggregate metric. However, this aggregate figure masks the fact that the i3-9320 wins every single benchmark listed in the head-to-head suite, while the i5-6600K’s average is buoyed by its Geekbench scores, which are not part of the direct comparison.

Architecture Differences

The two processors come from different generations of Intel’s 14 nm manufacturing process, though both share the same 14 nm node. The i5-6600K is built on the Skylake architecture, released in 2015, while the i3-9320 uses the Coffee Lake architecture, specifically the Coffee Lake Refresh generation, released in 2019. This four-year gap in development time explains much of the performance difference, as Coffee Lake benefits from refinements that Skylake lacks.

Both CPUs have four cores and four threads, but the similarities end there. The i5-6600K has a base clock of 3.50 GHz and a boost clock of 3.90 GHz, while the i3-9320 runs at 3.70 GHz base and 4.40 GHz boost. The i3-9320’s higher clocks are a significant factor in its benchmark dominance, particularly in single-threaded workloads where clock speed is paramount.

Cache configuration differs as well. The i5-6600K has 6 MB of shared L3 cache, while the i3-9320 offers 8 MB of shared L3 cache. Both have identical L1 and L2 cache sizes at 64 KB per core and 256 KB per core, respectively. The additional 2 MB of L3 cache in the i3-9320 provides a modest advantage in workloads that benefit from larger on-die data storage.

The integrated graphics also differ. The i5-6600K features HD Graphics 530, while the i3-9320 is equipped with UHD Graphics 630. Memory support is another point of divergence: the i5-6600K supports both DDR3 and DDR4 memory, whereas the i3-9320 only supports DDR4. The i3-9320 also has a higher memory bandwidth at 38.4 GB/s compared to the i5-6600K’s 34.1 GB/s.

The i3-9320’s die size is listed at 126 mm², while the i5-6600K’s die size is not provided. The i5-6600K has an unlocked multiplier, making it overclockable, while the i3-9320 does not. The i3-9320 also supports ECC memory, a feature absent from the i5-6600K. Power consumption favors the i3-9320, with a TDP of 62 watts versus the i5-6600K’s 91 watts, indicating greater efficiency per watt of performance.

FAQ

Q: Which processor is faster in multi-core workloads?

A: The Intel Core i3-9320 wins all multi-core benchmarks. In Cinebench R23 multicore, it scores 6254 versus the i5-6600K’s 5363, a 14.2% lead. Similar margins appear in Cinebench R15 and R20 multicore tests.

Q: Does the i5-6600K have any advantages in single-core performance?

A: No. The i3-9320 wins every single-core benchmark, including Cinebench R23 single-core with a score of 882 against the i5-6600K’s 757, a 14.2% difference.

Q: Are these processors comparable in overall average performance?

A: Yes, their average benchmark scores are nearly identical. The i5-6600K averages 1816, while the i3-9320 averages 1808, a difference of only 0.4% in favor of the i5-6600K.

Q: What are the clock speed differences between the two?

A: The i5-6600K has a base clock of 3.50 GHz and a boost clock of 3.90 GHz. The i3-9320 has a base clock of 3.70 GHz and a boost clock of 4.40 GHz.

Q: Do both processors support overclocking?

A: No. The i5-6600K has an unlocked multiplier, allowing overclocking. The i3-9320 has a locked multiplier, preventing overclocking.

Q: Which CPU has more L3 cache?

A: The i3-9320 has 8 MB of shared L3 cache, while the i5-6600K has 6 MB. Both have identical L1 and L2 caches at 64 KB and 256 KB per core.

The Verdict

The data leaves no room for ambiguity: the Intel Core i3-9320 is the superior processor in every direct benchmark comparison. It wins all six head-to-head tests, with consistent deltas of approximately 14% across both single-core and multi-core workloads. The i3-9320’s higher clock speeds, larger L3 cache, and newer Coffee Lake architecture give it a decisive edge over the Skylake-based i5-6600K.

The i5-6600K’s only statistical claim to relevance is its slightly higher average benchmark score of 1816 versus 1808, but this aggregate metric is misleading given that the i3-9320 wins every benchmark in the direct comparison suite. The i5-6600K’s unlocked multiplier offers overclocking potential, which could theoretically close the gap, but this advantage is speculative and not reflected in the stock benchmark data.

For users seeking maximum out-of-the-box performance, the i3-9320 is the clear choice. It also offers lower power consumption at 62 watts TDP versus 91 watts, ECC memory support, and a larger L3 cache. The i5-6600K’s sole practical advantage is its support for both DDR3 and DDR4 memory, which may appeal to those upgrading an older system without changing memory modules. However, on pure performance metrics, the i3-9320 wins decisively.

Specification Differences

The two processors differ in several key specifications. The i5-6600K has a base clock of 3.50 GHz and a boost clock of 3.90 GHz, while the i3-9320 runs at 3.70 GHz base and 4.40 GHz boost. The i3-9320 has a lower TDP of 62 watts compared to the i5-6600K’s 91 watts.

Cache sizes differ, with the i5-6600K offering 6 MB of shared L3 cache and the i3-9320 providing 8 MB. Memory support varies: the i5-6600K supports DDR3 and DDR4, while the i3-9320 only supports DDR4. Memory bandwidth also differs, with the i5-6600K at 34.1 GB/s and the i3-9320 at 38.4 GB/s.

The integrated graphics are different, with the i5-6600K featuring HD Graphics 530 and the i3-9320 using UHD Graphics 630. The i3-9320 supports ECC memory, while the i5-6600K does not. The i5-6600K has an unlocked multiplier, whereas the i3-9320’s multiplier is locked. The i3-9320 has a die size of 126 mm², while the i5-6600K’s die size is not listed. The architectures differ, with the i5-6600K on Skylake and the i3-9320 on Coffee Lake.

Where Each One Wins

The Intel Core i3-9320 wins in every benchmark category, making it the superior choice for all performance-oriented tasks. It dominates in single-core workloads in Cinebench R15, R20, and R23, with scores of 88, 370, and 882 respectively, versus the i5-6600K’s 76, 317, and 757. This makes it the better option for applications that rely heavily on single-threaded performance, such as older games or lightly threaded productivity software.

In multi-core workloads, the i3-9320 also wins, with Cinebench R15, R20, and R23 scores of 630, 2626, and 6254 against the i5-6600K’s 540, 2252, and 5363. This gives it an edge in multi-threaded tasks like video encoding, 3D rendering, and compilation, though the 4-core/4-thread configuration limits both CPUs in heavily parallel workloads.

The i5-6600K’s wins are limited to non-benchmark attributes. Its unlocked multiplier makes it the better choice for enthusiasts who plan to overclock and are willing to accept higher power consumption. Its support for DDR3 memory could be an advantage for users with existing DDR3 modules who want to avoid a memory upgrade. However, in terms of raw benchmark performance, the i3-9320 wins every single test, making it the definitive choice for anyone prioritizing speed and efficiency.